VILLIE-MORGON, France (AP) Time trial world champion Tony Martin dropped out of the Tour de France on Tuesday to focus on recovering from an injury in time for the London Olympics.

Martin broke the scaphoid bone of his left hand during the first stage on July 1. He stayed in the race, aiming for a possible win in the first long time trial.

But the powerful German had a flat in Monday's 25.8-mile time trial to Besancon and finished 12th.

"It's difficult for me to step out of the Tour and leave my teammates here to keep on fighting," Martin said. "But it's the right thing to do now, and I know that even the guys will understand. I will go home and I will try to recover as much as I can."

Everything went wrong for Martin from the start of the Tour. Before breaking his hand, he had a punctured tire in the opening prologue that dashed his hope of claiming the yellow jersey.

His main objective this season is winning the time trial at the London Games on Aug. 1 to add to the gold medal he claimed at the world championships last year.

Martin, who spent a lot of time at the back of the peloton since his injury, said he did not want to risk aggravating it when the race hit the Alps.

"I don't want things to get even worse going into the mountains," Martin said. "I cannot imagine sitting in the back of the peloton suffering every day a little bit more as I did during this week. I really tried, but now it's time to think about my complete recovery. I have still three weeks before the Olympics."

Omega Pharma Quick Step doctor Helge Riepenhof said Martin had to withdraw from the Tour to maximize his chances of performing well in London.

"From a medical point of view, it is now time to give the scaphoid fracture a chance to heal," he said in a statement. "We also have to avoid further issues to his body because of being limited in his movement while wearing a brace. This is the only possible decision to be able to perform at the London Olympics without damaging structures such as the lower back or knees."

Martin was expected to fly home later Tuesday.

The Tour peloton is enjoying a rest day before Wednesday's 10th stage from Macon to Bellegarde-sur-Valserine, the first Alpine leg featuring the grueling ascent of the Col du Grand Colombier.